How do i know if a girl like me after she rejected me to walk her brother home.?

[Minime]

so me and her friend have been talking on twitter for so long and she kept telling me her friend liked me. I liked her friend but i wasnt 100% sure she was saying the truth.It was summer and me and the girl i liked talked all summer. i told her i liked her and she said the same about me. I waited and then i asked her out. She said no because she had to walk her brother home. I would have been fine but she always walked with her friend and her friend could have walked her brother home. after it was like a YEAR! we werent really friends because she was to shy to talk to me. i always see her staring at me and i think she still likes me but i would not want to ask her out again because that would sound desperate. We are in different classes and she cant even be around me without looking down and not saying a word. What should i do because i still have a little feelings for her but they lesson every day? I dont know what to do? I atleast want to be friends but she cant even talk to me and she voids me?